If h(s) = (s ⁴ - 5)², then by the chain and power rule,
h'(s) = 2 (s ⁴ - 5) • (s ⁴ - 5)'
By the power rule,
(s ⁴ - 5)' = 4s ³
so that
h'(s) = 8s ³ (s ⁴ - 5)
… = 8s ⁷ - 40s ³
